Ad Breaks
The iOS Sender SDK provides support for Ad Breaks and companion ads within a given media stream.
See the Web Receiver Ad Breaks Overview for more information on how Ad Breaks work.
While breaks can be specified on both the sender and receiver, it is recommended for them to be specified on the Web Receiver and Android TV Receiver to maintain consistent behavior across platforms.
On iOS, specify Ad Breaks in a load command using
GCKAdBreakClipInfo
and GCKAdBreakInfo
:
let breakClip1Builder = GCKAdBreakClipInfoBuilder(adBreakClipID: "bc0") breakClip1Builder.title = "Clip title" if let posterUrl = URL(string: "https://www.some.url") { breakClip1Builder.posterURL = posterUrl } breakClip1Builder.duration = 60 breakClip1Builder.whenSkippable = 5 // Set this field so that the ad is skippable let breakClip1 = breakClip1Builder.build() let breakClip2 = ... let breakClip3 = ... let break1 = GCKAdBreakInfoBuilder(adBreakID: "b0", adBreakClipIds: ["bc0", "bc1", "bc2"]).build() let mediaInfoBuilder = GCKMediaInformationBuilder(entity: "entity") ... mediaInfoBuilder.adBreaks = [break1] mediaInfoBuilder.adBreakClips = [breakClip1, breakClip2, breakClip3] ... mediaInformation = mediaInfoBuilder.build() let mediaLoadRequestDataBuilder = GCKMediaLoadRequestDataBuilder() mediaLoadRequestDataBuilder.mediaInformation = mediaInformation sessionManager.currentSession?.remoteMediaClient?.loadMedia(with: mediaLoadRequestDataBuilder.build())
GCKAdBreakClipInfoBuilder *breakClipInfoBuilder = [[GCKAdBreakClipInfoBuilder alloc] initWithAdBreakClipID:@"bc0"]; breakClipInfoBuilder.title = @"Clip title"; breakClipInfoBuilder.posterURL = [[NSURL alloc] initWithString:@"https://www.some.url"]; breakClipInfoBuilder.duration = 60; breakClipInfoBuilder.whenSkippable = 5; GCKAdBreakClipInfo *breakClip1 = breakClipInfoBuilder.build; GCKAdBreakClipInfo *breakClip2 = ... GCKAdBreakClipInfo *breakClip3 = ... GCKAdBreakInfo *break1 = [[GCKAdBreakInfoBuilder alloc] initWithAdBreakID:@"b0" adBreakClipIds:@[@"bc0", @"bc1", @"bc2"]].build; GCKMediaInformationBuilder *mediaInfoBuilder = [[GCKMediaInformationBuilder alloc] initWithEntity:@"entity"]; ... mediaInfoBuilder.adBreaks = @[break1]; mediaInfoBuilder.adBreakClips = @[breakClip1, breakClip2, breakClip3]; ... self.mediaInformation = [mediaInfoBuilder build]; GCKMediaLoadRequestDataBuilder *mediaLoadRequestDataBuilder = [[GCKMediaLoadRequestDataBuilder alloc] init]; mediaLoadRequestDataBuilder.mediaInformation = self.mediaInformation; // Send a load request to the remote media client. GCKRequest *request = [self.sessionManager.currentSession.remoteMediaClient loadMediaWithLoadRequestData:[mediaLoadRequestDataBuilder build]];
Variable playback rate
Your app can display and change the playback rate for the current media item.
You are able to set the rate using -[setPlaybackRate:]
or
-[setPlaybackRate:customData:]
of the
GCKRemoteMediaClient
,
access the GCKUIPlaybackRateController
using playbackRateController
of the
GCKUIMediaController
,
and display the current playback rate using playbackRate
of the
GCKUIPlaybackRateController
.
Sample code
The following two files implement GCKUIPlaybackRateController
which controls
the playback rate using a segmented control that has "normal", "half speed", and
"double speed" buttons:
import GoogleCast /** * An implementation of GCKUIPlaybackRateController that controls playback rate * using a segmented control that has "normal", "half speed", and "double speed" * buttons. */ class SegmentedButtonPlaybackRateController: GCKUIPlaybackRateController { static let kSegmentNormal = 0; static let kSegmentHalfSpeed = 1; static let kSegmentDoubleSpeed = 2; var segmentedControl: UISegmentedControl! override var playbackRate: Float { didSet { var buttonIndex = 0 // Map the playback rate to one of our three supported speeds. if playbackRate == 1.0 { buttonIndex = SegmentedButtonPlaybackRateController.kSegmentNormal } else if playbackRate < 1.0 { buttonIndex = SegmentedButtonPlaybackRateController.kSegmentHalfSpeed } else { buttonIndex = SegmentedButtonPlaybackRateController.kSegmentDoubleSpeed } segmentedControl?.selectedSegmentIndex = buttonIndex } } override var inputEnabled: Bool { didSet { segmentedControl?.isEnabled = inputEnabled } } /** * Designated initializer. * * @param segmentedControl The segmented control for changing/displaying the * playback rate. */ convenience init(_ segmentedControl: UISegmentedControl) { self.init() self.segmentedControl = segmentedControl; segmentedControl.addTarget(self, action: #selector(segmentedControlTapped(sender:)), for: UIControl.Event.valueChanged) } @objc func segmentedControlTapped(sender: UISegmentedControl) { var playbackRate: Float = 1.0 switch segmentedControl?.selectedSegmentIndex { case SegmentedButtonPlaybackRateController.kSegmentHalfSpeed: playbackRate = 0.5; case SegmentedButtonPlaybackRateController.kSegmentDoubleSpeed: playbackRate = 2.0; case SegmentedButtonPlaybackRateController.kSegmentNormal: fallthrough default: playbackRate = 1.0; } self.playbackRate = playbackRate } }
SegmentedButtonPlaybackRateController.h
#import <GoogleCast/GoogleCast.h> #import <UIKit/UIKit.h> /** * An implementation of GCKUIPlaybackRateController that controls playback rate * using a segmented control that has "normal", "half speed", and "double speed" * buttons. */ @interface SegmentedButtonPlaybackRateController : GCKUIPlaybackRateController /** * Designated initializer. * * @param segmentedControl The segmented control for changing/displaying the * playback rate. */ - (instancetype)initWithSegmentedControl:(UISegmentedControl *)segmentedControl; @end
SegmentedButtonPlaybackRateController.m
#import "SegmentedButtonPlaybackRateController.h" @interface SegmentedButtonPlaybackRateController () { UISegmentedControl *_segmentedControl; } @end static const NSInteger kSegmentNormal = 0; static const NSInteger kSegmentHalfSpeed = 1; static const NSInteger kSegmentDoubleSpeed = 2; @implementation SegmentedButtonPlaybackRateController - (instancetype)initWithSegmentedControl:(UISegmentedControl *)segmentedControl { if (self = [super init]) { _segmentedControl = segmentedControl; [_segmentedControl addTarget:self action:@selector(segmentedControlTapped:) forControlEvents:UIControlEventValueChanged]; } return self; } - (void)setPlaybackRate:(float)playbackRate { [super setPlaybackRate:playbackRate]; NSInteger buttonIndex = 0; // Map the playback rate to one of our three supported speeds. if (playbackRate == 1.0) { buttonIndex = kSegmentNormal; } else if (playbackRate < 1.0) { buttonIndex = kSegmentHalfSpeed; } else { buttonIndex = kSegmentDoubleSpeed; } _segmentedControl.selectedSegmentIndex = buttonIndex; } - (void)setInputEnabled:(BOOL)inputEnabled { _segmentedControl.enabled = inputEnabled; [super setInputEnabled:inputEnabled]; } - (void)segmentedControlTapped:(id)sender { float playbackRate; switch (_segmentedControl.selectedSegmentIndex) { case kSegmentHalfSpeed: playbackRate = 0.5; break; case kSegmentDoubleSpeed: playbackRate = 2.0; break; case kSegmentNormal: default: playbackRate = 1.0; break; } self.playbackRate = playbackRate; } @end
Add a custom channel
The Cast framework provides two ways to create a channel to send custom messages to a Web Receiver:
GCKCastChannel
is meant to be subclassed to implement non-trivial channels that have associated state.GCKGenericChannel
is provided as an alternative to subclassing; it passes its received messages to a delegate so that they can be processed elsewhere.
Here is an example of a GCKCastChannel
implementation:
class HGCTextChannel: GCKCastChannel { override func didReceiveTextMessage(_ message: String) { print("received message: \(message)") } }
HGCTextChannel.h
#import <GoogleCast/GCKCastChannel.h> @interface HGCTextChannel : GCKCastChannel @end
HGCTextChannel.m
#import "HGCTextChannel.h" @implementation HGCTextChannel - (void)didReceiveTextMessage:(NSString*)message { NSLog(@"received message: %@", message); } @end
A channel can be registered at any time; if the session is not currently in a connected state, the channel will automatically become connected when the session itself is connected, provided that the channel's namespace is present in the Web Receiver app metadata's list of supported namespaces.
Each custom channel is defined by a unique namespace and must start with the
prefix urn:x-cast:
, for example, urn:x-cast:com.example.custom
. It is
possible to have multiple custom channels, each with a unique namespace. The
Web Receiver app can also send and receive
messages
using the same namespace.
var error: GCKError? let textChannel = HGCTextChannel.init(namespace: "urn:x-cast:com.google.cast.sample.helloworld") sessionManager.currentCastSession?.add(textChannel) textChannel.sendTextMessage("Hello World", error: &error) if error != nil { print("Error sending text message \(error.debugDescription)") }
NSError *error; HGCTextChannel *textChannel = [[HGCTextChannel alloc] initWithNamespace:@"urn:x-cast:com.google.cast.sample.helloworld"]; [sessionManager.currentCastSession addChannel:textChannel]; [textChannel sendTextMessage:@"Hello World" error:&error]; if (error != nil) { NSLog(@"Error sending text message: %@", error); }
To provide logic that needs to execute when a particular channel becomes
connected or disconnected, override the -[didConnect]
and -[didDisconnect]
methods if using
GCKCastChannel
, or
provide implementations for the -[castChannelDidConnect:]
and
-[castChannelDidDisconnect:]
methods of the
GCKGenericChannelDelegate
if using GCKGenericChannel
.
Supporting Autoplay
Override image selection and caching
Various components of the framework (namely the Cast dialog, the mini
controller, the expanded controller, and the
GCKUIMediaController
if so configured) will display artwork for the currently casting media. The URLs
to the image artwork are typically included in the
GCKMediaMetadata
for the media, but the sender app may have an alternate source for the URLs.
The
GCKUIImagePicker
protocol defines a means for selecting an appropriate image for a given usage
and desired size. It has a single method, -[getImageWithHints:fromMetadata:]
,
which takes a
GCKUIImageHints
object and a
GCKMediaMetadata
object as parameters, and returns a
GCKImage
object as a
result. The framework provides a default implementation of
GCKUIImagePicker
which always selects the first image in the list of images in
the GCKMediaMetadata
object, but the app can provide an alternate
implementation by setting the imagePicker
property of the
GCKCastContext
singleton.
The
GCKUIImageCache
protocol also defines a means of caching images that are downloaded by the
framework using HTTPS. The framework provides a default implementation of
GCKUIImageCache
which stores downloaded image files in the app's cache
directory, but the app can provide an alternate implementation by setting the
imageCache
property of the
GCKCastContext
singleton.
Next steps
This concludes the features that you can add to your iOS Sender app. You can now build a sender app for another platform (Android or Web), or build a Web Receiver.